title: Threonine, tryptophan and histidine requirements of immature beagle dogs.
abstract: The threonine, tryptophan and histidine requirements of growing male Beagle dogs were determined using diets containing the equivalent of 14% protein as crystalline L-amino acids. For each amino acid the requirement was taken to be the minimum dietary quantity required for optimal growth, feed efficiency and nitrogen retention. In experiment 1 the threonine requirement was found to be provided by 0.52% or more dietary threonine. In experiments 2 and 3 the minimal dietary tryptophan and histidine requirements of immature dogs were estimated as 0.17 and 0.21%, respectively. The requirements for threonine and tryptophan are similar to those for growing rats. However, the histidine requirement of Beagles appears to be lower than that of rats.
mesh_terms: D000596:Amino Acids / Q000008:administration & dosage; D000818:Animals; D001806:Blood Urea Nitrogen; D001835:Body Weight; D004044:Dietary Proteins / Q000008:administration & dosage; D004285:Dogs / Q000254:growth & development*; D006639:Histidine / Q000502:physiology*; D008297:Male; D009584:Nitrogen / Q000378:metabolism; D009747:Nutritional Physiological Phenomena; D009751:Nutritional Requirements; D013912:Threonine / Q000502:physiology*; D014364:Tryptophan / Q000502:physiology*
chemical_list: D000596:Amino Acids; D004044:Dietary Proteins; D013912:Threonine; D006639:Histidine; D014364:Tryptophan; D009584:Nitrogen